Mammography is the recommended screening tool for the early detection of breast cancer. The government’s national screening program, BreastScreen Australia, invites women aged 50–74 to undergo free mammograms every two years. Women aged 40–49 and those aged over 74 can also be screened free of charge, however they are not sent invitation letters.

Cancer Council Australia recommends that women who are eligible for BreastScreen Australia participate in the program, provided they are aware of the benefits and the risks.

Although screening with mammography is shown to reduce breast cancer mortality, it can also cause harm. A recent review of BreastScreen Australia estimated that the program reduces breast cancer mortality by between 21 and 28 per cent. While this is significant, mammography can also lead to overdiagnosis. Overdiagnosis describes the diagnosis of cancers which, undetected, would not have caused symptoms or health problems in the patient. This can lead to unnecessary treatments and distress. Overdiagnosis occurs because mammography cannot accurately distinguish between potentially fatal cancers and less harmful cancers.